you have to execute the following command:
git clone git://repo.or.cz/ncmpcpp.git
then enter downloaded folder:
cd ncmpcpp
and regenerate configure script and makefiles by typing:
./autogen.sh
if it succeeded without errors, now it's time to run:
./configure YOUR_CONFIGURE_OPTS (you can see them by typing ./configure --help)
make
make install
However, if you want to install it from tarball, download and unpack it:
tar pjvxf TARBALL_FILENAME
then enter unpacked directory and type:
./configure YOUR_CONFIGURE_OPTS
make
make install
congratulations, you have successfully installed ncmpcpp :)